extensions/ext: Add VK_EXT_headless_surface instance extension

Changelog.md

@@ -4,6 +4,12 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## Unreleased
+
+### Added
+
+- Added `VK_EXT_headless_surface` instance extension (#589)
+
 ## [0.36.0] - 2022-02-21
 
 ### Changed

ash/src/extensions/ext/headless_surface.rs

@@ -0,0 +1,52 @@
+use crate::prelude::*;
+use crate::vk;
+use crate::RawPtr;
+use crate::{Entry, Instance};
+use std::ffi::CStr;
+use std::mem;
+
+/// <https://www.khronos.org/registry/vulkan/specs/1.3-extensions/man/html/VK_EXT_headless_surface.html>
+#[derive(Clone)]
+pub struct HeadlessSurface {
+    handle: vk::Instance,
+    fp: vk::ExtHeadlessSurfaceFn,
+}
+
+impl HeadlessSurface {
+    pub fn new(entry: &Entry, instance: &Instance) -> Self {
+        let handle = instance.handle();
+        let fp = vk::ExtHeadlessSurfaceFn::load(|name| unsafe {
+            mem::transmute(entry.get_instance_proc_addr(handle, name.as_ptr()))
+        });
+        Self { handle, fp }
+    }
+
+    /// <https://www.khronos.org/registry/vulkan/specs/1.3-extensions/man/html/vkCreateHeadlessSurfaceEXT.html>
+    pub unsafe fn create_headless_surface(
+        &self,
+        create_info: &vk::HeadlessSurfaceCreateInfoEXT,
+        allocation_callbacks: Option<&vk::AllocationCallbacks>,
+    ) -> VkResult<vk::SurfaceKHR> {
+        let mut surface = mem::zeroed();
+        self.fp
+            .create_headless_surface_ext(
+                self.handle,
+                create_info,
+                allocation_callbacks.as_raw_ptr(),
+                &mut surface,
+            )
+            .result_with_success(surface)
+    }
+
+    pub fn name() -> &'static CStr {
+        vk::ExtHeadlessSurfaceFn::name()
+    }
+
+    pub fn fp(&self) -> &vk::ExtHeadlessSurfaceFn {
+        &self.fp
+    }
+
+    pub fn instance(&self) -> vk::Instance {
+        self.handle
+    }
+}

ash/src/extensions/ext/mod.rs

@@ -8,6 +8,7 @@ pub use self::debug_utils::DebugUtils;
 pub use self::extended_dynamic_state::ExtendedDynamicState;
 pub use self::extended_dynamic_state2::ExtendedDynamicState2;
 pub use self::full_screen_exclusive::FullScreenExclusive;
+pub use self::headless_surface::HeadlessSurface;
 pub use self::metal_surface::MetalSurface;
 pub use self::physical_device_drm::PhysicalDeviceDrm;
 pub use self::private_data::PrivateData;
@@ -23,6 +24,7 @@ mod debug_utils;
 mod extended_dynamic_state;
 mod extended_dynamic_state2;
 mod full_screen_exclusive;
+mod headless_surface;
 mod metal_surface;
 mod physical_device_drm;
 mod private_data;